According to my textbook (Hansen & Quinn's Greek: An Intensive Coure, which is limited to Attic dialect) - no.
Indeed, on numerous occasions I didn't recognise that a sentence was a question until I came to the closing punctuation!

Bringing up the subject spacing again (I've mentioned this in other threads) I have discovered that Greek with breathings and accents appears perfectly when the text is LARGE, but horribly misspaced when it is normal.
Don't ask me why because I wouldn't even know where to start thinking about looking for a place to find a reason but... I wonder if Will and Jeff could or would consider making the default Greek text size 18. It IS easier to read and if all the bits come out in a decent fashion then many misreads would be avoided.